Due to unbalanced applications of chemical fertilizers;
- Soil health is deteriorating
- Soil organic matter is reducing
- Crop productivity is declining
Therefore, it is the time to shift from Conventional farming to organic farming. In this regard, application of human urine is gaining polarity as a fertilizer.
Objective of this article is to investigate the possibility of reuse of human urine as natural fertilizer for Corn crop.
To investigate, we have to collect following data;
- Selection of crop – Corn crop is selected
- Per hectare NPK requirement of the crop
- NPK concentration in human urine
- Cost of commercial fertilizer
- Transportation cost of Urine
NPK Requirement of Corn Crop
Requirement of Micro nutrient and Macro nutrient is given in the table below for 5.5. T/ha grain;
Table 1: Nutrient requirements (kg/ha) of Corn per 5.5 T/ha grain
Human urine is a liquid waste product of the human body secreted by the kidneys by a process of filtration from blood called urination and excreted through the urethra. As urine is produced after filtration of the blood in the kidneys, it contains low-molecular-weight compounds as proteins are not filtered.
Each individual produces 1–1.5 L of urine per day in 4–5 times and an adult person excretes on average of 500 L urine per year. However, children urinates about half of that of the adults amount.
Of the human excreta, urine contains the major part of the daily excretion of nitrogen (N), phosphorous (P) and potassium (K) contributing 88%, 67% and 73%, respectively. However, the composition of human urine varies from person to person and from region to region depending on his/her feeding habits, the amount of drinking water consumed, physical activities, body size, and environmental factors. The table below represents micro & macro nutrient composition of human urine cited in various literatures;
Table 2: Micro and Macro Nutrients present in Human Urine
|Sr. No.||Nutrient||Concentration (min - max)|
|1.||Total Nitrogen (g/L)||1.795 - 17.5|
|2.||Urea||85 % of Total Nitrogen|
|3.||Total Phosphorus (g/L)||0.15 - 3.7|
|4.||Potassium (g/L)||0.59 - 3.3|
|5.||S (g/L)||0.175 - 0.225|
|6.||Mg (mg/L)||1.500 - 1.630|
From detailed literature review, the following data is used for calculations;
|TN||TP||K||Urea||Per capita Urine|
|8.0 g/L||0.75 g/L||1.2 g/L||6.8 g/L||1.0 L/cap. Day|
Thus the quantity of required for one hectare area can be calculated as;
|Quantity for TN||Quantity for TP||Quantity for K||Quantity for Urea|
|15,125 L/ha||25,333 L/ha||20,000 L/ha||17,491 L/ha|
|15.125 m3/ha||25.333 m3/ha||20.00 m3/ha||17.491 m3/ha|
The cost of commercial fertilizers is taken from National Fertilizer Development Center which was last updated in 2011.
|Sr. No.||Fertilizer||Quantity required|
|Cost per 50 kg||Cost /ha|
|2.||DAP (46% of P)||19||3236||3236|
|3.||Sulfate of Potash, SOP, (41 % K)||24||2807||2807|
|Total Cost of commercial Fertilizer per hectare||Rs. 8955/-|
Urine Transportation Cost
No literature is available regarding transportation cost. Therefore, a local company is contacted to get per km cost.
- Per km cost for freight vehicle (7 m3) is Rs. 25/km.
The graphs below are representing the comparison between Commercial Fertilizer & Human Urine.
- Human Urine can be used for meeting nutrient requirement of Crops.
- Figure 1 to 4 represents breakeven points for various possibilities of human urine usage. Breakeven point represents the transportation distance of human urine distance beyond which the usage of human urine is less expensive. The summary of breakeven point is as under;
|Utilization||For N only||For P only||For K only||For NPK|
|Break-even||38 km||32 km||35 km||90 km|